Effects of plastic film mulching with drip irrigation on N2O and CH4 emissions from cotton fields in arid land

SUMMARYTo evaluate the effects of a modern cultivation system of plastic film mulching with drip irrigation (MD) on soil greenhouse gas fluxes, methane (CH4) and nitrous oxide (N2O) fluxes were quantified and contrasted in an MD system and a traditional system of mulch-free flood-irrigated (MFF) cotton (Gossypium hirsutum L.) in fields of northwest China. The results showed that soil N2O flux and the absorption rate of CH4 were lower in the MD than the MFF sites. A possible reason for the higher CH4 emissions at MD sites was that the relatively low gaseous oxygen (O2) availability and high ammonium (NH4+) content in the MD soil increased CH4 generation by methanogens and decreased CH4 oxidation by methanotrophs. The lower N2O in the MD sites may be due to an increase of soil denitrification by Thiobacillus denitrificans that reduced some nitrous compounds further into nitrogen gas (N2). Taking into account the global warming potentials of CH4 and N2O in a 100-year time horizon, during the entire growth period, the contribution of CH4 to the greenhouse effect was significantly lower than N2O in these two treatments. Considering these two greenhouse gas fluxes together, a transition from non-mulching cultivation to mulching cultivation could reduce atmospheric emissions by c. 20 g CO2 e m2/season. Based on these findings and previous studies, it can be concluded that mulched-drip irrigation cultivation is a good way to decrease the emission of greenhouse gases and reduce the global warming impact of arid farmlands.

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Plastic film mulching with drip irrigation promotes maize (Zea mays L.) yield and water-use efficiency by improving photosynthetic characteristics

Archives of Agronomy and Soil Science ◽

10.1080/03650340.2020.1718662 ◽

2020 ◽

pp. 1-14

Author(s):

Chuanjuan Wang ◽

Yanqun Zhang ◽

Jiandong Wang ◽

Di Xu ◽

Shihong Gong ◽

...

Keyword(s):

Zea Mays ◽

Water Use Efficiency ◽

Water Use ◽

Drip Irrigation ◽

Zea Mays L ◽

Photosynthetic Characteristics ◽

Plastic Film ◽

Plastic Film Mulching ◽

Use Efficiency ◽

Film Mulching

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Reducing yield-scaled global warming potential and water use by rice plastic film mulching in a winter flooded paddy field

European Journal of Agronomy ◽

10.1016/j.eja.2020.126007 ◽

2020 ◽

Vol 114 ◽

pp. 126007

Author(s):

Guangbin Zhang ◽

Yuting Yang ◽

Qiong Huang ◽

Jing Ma ◽

Haiyang Yu ◽

...

Keyword(s):

Global Warming ◽

Water Use ◽

Global Warming Potential ◽

Paddy Field ◽

Plastic Film ◽

Plastic Film Mulching ◽

Film Mulching

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Influence of conservation tillage on Greenhouse gas fluxes and crop productivity in spring-wheat agroecosystems on the Loess Plateau of China

PeerJ ◽

10.7717/peerj.11064 ◽

2021 ◽

Vol 9 ◽

pp. e11064

Author(s):

Abdul-Rauf Malimanga Alhassan ◽

Chuanjie Yang ◽

Weiwei Ma ◽

Guang Li

Keyword(s):

Climate Change ◽

Global Warming ◽

Greenhouse Gas ◽

Loess Plateau ◽

Crop Productivity ◽

Conventional Tillage ◽

Straw Mulch ◽

No Till ◽

Gas Fluxes ◽

Greenhouse Gas Fluxes

The effects of climate change such as dry spells, floods and erosion heavily impact agriculture especially smallholder systems on the Northwestern Loess Plateau of China. Nonetheless agriculture also contributes to global warming through the emission of greenhouse gases such as CO2, CH4 and N2O. Yet this complex conundrum can be alleviated and mitigated through sound soil and water management practices. Despite considerable literature on Conservation Agriculture (CA) as a strategy to improve the resilience and mitigation capacity of agroecosystems, there is still paucity of information on the impacts of CA on crop production and environmental quality on the Plateau. In order to fill this gap this study examined the effects of no-till and straw mulch on crop productivity and greenhouse gas fluxes in agroecosystems on the Plateau where farmers’ common practice of conventional tillage (CT) was tested against three CA practices: conventional tillage with straw mulch (CTS), no-till (NT) and no-till with straw mulch (NTS). The results indicated that all three CA practices (CTS, NT and NTS) markedly increased soil water content (SWC), soil organic carbon (SOC) and soil total nitrogen (STN) but reduced soil temperature (ST). Average grain yields were 854.46 ± 76.51, 699.30 ± 133.52 and 908.18±38.64 kg ha-1 respectively under CTS, NT and NTS indicating an increase by approximately 33%, 9% and 41% respectively compared with CT (644.61 ± 76.98 kg ha−1). There were significant (p < 0.05) reductions of Net CO2 emissions under NT (7.37 ± 0.89 tCO2e ha−1y−1) and NTS (6.65 ± 0.73 tCO2e ha-1y-1) compared with CTS (10.65 ± 0.18 tCO2e ha−1y−1) and CT (11.14 ± 0.58 tCO2e ha−1y−1). All the treatments served as sinks of CH4but NTS had the highest absorption capacity (−0.27 ± 0.024 tCO2e ha−1y−1) and increased absorption significantly (p < 0.05) compared with CT (−0.21 ± 0.017 tCO2e ha−1y−1); however, CA did not reduce emissions of N2O. These had an influence on Global warming potential (GWP) as NT and NTS resulted in significant reduction in net GWP. Grain yield was significantly correlated positively with SOC and STN (p < 0.05); ecosystem respiration was also significantly correlated with SWC and ST while CH4 flux was highly correlated with ST (p < 0.001). Crop yield and GHG responses to CA were controlled by soil hydrothermal and nutrient changes, thus improving these conditions through adoption of sustainable soil moisture improvement practices such as no-till, straw mulch, green manuring, contour ploughing and terracing can improve crop resilience to climate change and reduce GHG emissions in arid and semi-arid regions.

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EFFECTS OF FERTILIZATION ON POREWATER NUTRIENTS, GREENHOUSE-GAS EMISSIONS AND RICE PRODUCTIVITY IN A SUBTROPICAL PADDY FIELD

Experimental Agriculture ◽

10.1017/s0014479718000078 ◽

2018 ◽

Vol 55 (3) ◽

pp. 395-411 ◽

Cited By ~ 1

Author(s):

WEIQI WANG ◽

JORDI SARDANS ◽

CHUN WANG ◽

CHUAN TONG ◽

QINYANG JI ◽

...

Keyword(s):

Global Warming ◽

Greenhouse Gas Emissions ◽

Greenhouse Gas ◽

Rice Yield ◽

Scientific Basis ◽

Double Fertilization ◽

Gas Emissions ◽

Gas Fluxes ◽

Greenhouse Gas Fluxes ◽

Porewater Nutrients

SUMMARYSuitable fertilization is crucial for the sustainability of rice production and for the potential mitigation of global warming. The effects of fertilization on porewater nutrients and greenhouse-gas fluxes in cropland, however, remain poorly known. We studied the effects of no fertilization (control), standard fertilization and double fertilization on the concentrations of porewater nutrients, greenhouse-gas fluxes and emissions, and rice yield in a subtropical paddy in southeastern China. Double fertilization increased dissolved NH4+ in porewater. Mean CO2 and CH4 emissions were 13.5% and 7.4%, and 20.4% and 39.5% higher for the standard and double fertilizations, respectively, than the control. N2O depositions in soils were 61% and 101% higher for the standard and double fertilizations, respectively, than the control. The total global warming potentials (GWPs) for all emissions were 14.1% and 10.8% higher for the standard and double fertilizations, respectively than the control, with increasing contribution of CH4 with fertilization and a CO2 contribution > 85%. The total GWPs per unit yield were significantly higher for the standard and double fertilizations than the control by 7.3% and 10.9%, respectively. The two levels of fertilization did not significantly increase rice yield. Prior long-term fertilization in the paddy (about 20 years with annual doses of 95 kg N ha−1, 70 kg P2O5 ha−1 and 70 kg K2O ha−1) might have prevented these fertilizations from increasing the yield. However, fertilizations increased greenhouse-gas emissions. This situation is common in paddy fields in subtropical China, suggesting a saturation of soil nutrients and the necessity to review current fertilization management. These areas likely suffer from unnecessary nutrient leaching and excessive greenhouse-gas emissions. These results provide a scientific basis for continued research to identify an easy and optimal fertilization management solution.

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